Copy Protected Audio CD's

Considering the number of Audio CD's that have passed through my hands, I'm surprised I've never run across one of these before - but that's life .

An aquaintance asked me to look at a CD he owns (Cockahoop by Cerys Matthews - Warner Bros 2564 60306 2) claiming he could play on an ordinary CD player, but not on his computer.... and he's right, I get the same result!

I did a bit of checking around and it seems that some copies of this disc were copy-protected - although I have yet to find anyone who knows just what sort of protection is involved - and this is, indeed, the end result.

Anyone here know more about this?

A good place to start looking are: http://www.fatchuck.com/z3.html and http://www.cdmediaworld.com/hardware/cdrom/cd_protections.shtml

Following there to c't gives this: http://www.heise.de/ct/cd-register/default.shtml?s=cd&id=1940&titel=cockahoop

Looks as it is cds100

Thank you very much.  There's a ton of stuff I need to read about in those links alone .

Just to say, after reading through all (well, some) of that stuff, I have now managed to produce a non-protected copy of the disc concerned.

Thanks again